What is the difference between sip phones and IP enabled phones?

SIP is one (and arguably the most popular and hence the most likely to be vendor independent) protocol of many (as enumerated by Paul) that does signaling to make phone calls happen.

If you see a protocol cake diagram, SIP sits on top of IP (as in, it uses IP underneath to move things around.)

Hence, if the phone supports SIP, it certainly supports IP.
However, if it supports IP, it may/may not support SIP.

If it is "merely" IP-enabled, it may use one of the industry wide protocols that Paul mentioned (which in fairness may still be manufacturer independent.) There is a risk however that the protocol it uses could be proprietary (like Skype or Skinny or something made by the manufacturer) and hence tie you in to the vendor.

All this to say that, "IP enabled" is insufficient information to indicate what protocol it is using or to say for a fact if it is vendor independent.

You may want to sidestep the SIP/IP question for a moment and ask the vendor exactly what you asked on this forum and then check if it's true.

Ask the supplier if the phones will work with a PBX from other vendors and then see if that PBX supports other phones as well. You should ask them this question even for SIP enabled claims to see if you could put in an Asterisk PBX or a PBX from a different vendor that talks SIP and have the phones work with it.

Hope that helps.

A SIP phone is IP enabled. Ip enabled phones have the ability to use the Internet Protocol between the end points and the host.

However, if you draw a comparison to cell phones, they come in several flavors. We had analog cell phones, we had TDMA, we had CDMA, and GSM.

GSM has become the emerging standard that most (not all) carriers are driving to. It is based on world wide accepted standards.

SO to is sip. It is an IP enabled telephone that uses the SIP signalling standard between its end points. This protocol at least gives a change of interoperability between different manufacturers.

A phone that is IP enabled, doesn't necessarily have interoperability with others unless it has a standard that it adheres to. Nortel's Unistem is an good example of an IP enabled device that is proprietary and doesn't necessarily interoperate with other devices.

Interoperability is going to be the biggest difference. SIP technology works to assure all packets travel the same path which can enhance call quality.

IP phones let you dial directly to another IP phone using the IP address of the phone over the network or internet without a provider or any system or IPPBX. SIP phones allow you to utilize a provider offering telephone number termination that will allow you to recieve and make calls over the internet or network to and from regular old telephones. Some proprietary systems have their own version of an IP phone. Most phones have both capabilities. I suggest the Linksys SPA phones and if you need a IPPBX, IVR etc either a simple Linksys system or for more features an asterisk Free/PBX on a regular old PC or server.

Hi, this is always a great question and there is no single answer. Recently in a webseminar a vendor of IP phones said, "one phone call does not mean the next call will work." That being said, the SIP Forum www.sipforum.org has many members of SIP phones and has worked tirelessly to get interoperability between devices. That being said, there was an announcement just today for a proprietary IP phoneset solution and when I asked "is this a SIP phoneset?" The answer was no.
Given that IP and SIP phones are not expensive, buying a few that you think you will use and testing them in your own test labs, is a good investment now and in the future.
Of course, if you want to learn more about the "inside" of SIP, there are hundreds of tutorials at www.techtionary.com and I am always glad to explain more.
Cheers,
Tom

You have to be aware of a couple of points not really clear from the above comments. Other than an IP enabled phone obviously uses IP as stated above, I think what you really are getting at is; what's the difference in operation and long term prospects...
In fact most manufacturers such as Siemens have two software loads to their IP devices, these IP phones are designed as IP phones not cobbled together from TDM devices, as I'm sure are all manufacturers’ devices.
With the proprietary software load the phone can be used on a IP enabled PBX and is proprietary to the provider, this has the advantage of allowing allot more integration between the IP-PBX and the phone; as all the features of the system are available on the device without having to configure the device as a separate entity. By this I mean the intelligence of the system is extended to the IP-phone by encapsulating the enhanced signaling (proprietary) in an IP packet to the phone. In this way almost no setup other than the IP address need be set in the device... IP-PBX’s almost always have a vast array of features, and this must be considered against the lesser feature rich SIP only soft switch.
You could have a SIP load on a device working on a IP-PBX such as a Siemens Hipath 3000\ 4000 however it requires setting up the device independently of the system it is connected to. By this I mean the system cannot pass all the features to the phone over SIP as SIP simply doesn’t support all the settings available on the system. For it to know of the system features you must manually setup the phone device.
If you opt for a SIP software load on the phone, and are using a Pure Native SIP soft switch then you’re open to use firstly any device that uses SIP and any soft switch for that matter.
Although Siemens SIP handsets have a few more features compared to other sip phones, one of which is facilitating a second registration that allows for survivability. I would base any decisions by comparing the benefits of both platforms; pure SIP vs IP-PBX with its proprietary phones; it's not simply clear cut SIP is better; it depends on its use.
Although if you purchased a Siemens IP phone for example with a Siemens IP-PBX, you could simply switch to a Siemens OSV SIP system and just load the SIP software image on the phone; in reality you could use a Siemens Optipoint or Openstage phone on any fully compliant SIP system; these devices are sold with for use on any sip system.
In the long term this protects the investment in devices on a large deployment as so long as the core system adheres to the SIP standard then the phones will work with any system.

I Hope this was informative.
Darren

SIP (Session Initiation Protocol) is one way (protocol) to transmit voice over an IP network. It happens to probably be the most common way. (other protocols include MGCP, SCCP, H323...)

An analogy to your question would be like asking: "Should I buy a car with an engine or should I buy a Hybrid?" Well, Hybrid cars have engines...

I know that's a bit of a stretch analogy... but 'SIP' phones are 'IP enabled' - and most IP phones use SIP... (Cisco IP Phones use SIP, MGCP, or SCCP (standard))

The question to ask about any IP phone is: "What Protocols does it support?" the most common answer will include "SIP"

Paul:

If you haven't already purchased a phone system, you might want to think about purchasing one from a carrier-neutral reseller.

WCI, Inc. is a Seattle-based telecommunications consulting that specializes in carrier-neutral telecom solutions. They consult with you on your business's needs to find the best, most cost-effective telecom solution for you.

They then set up that solution using technologies from different providers such as AT & T, Sprint, Qwest, Verizon, etc. This solution will save you money over buying all your solutions from the same carrier.

WCI is using SIP Trunking for setting up Local Dialtone and Long Distance services for companies with multiple locations in different states. It is easier and more cost efficient to connect all their remote business sites using SIP Trunking.

Below is a link to a .pdf on my web site for a product data sheet that I wrote for WCI. This data sheet explains how WCI uses SIP Trunking in setting up long distance services.

http://www.strategicwordsmith.biz/wcisiplongdistance.pdf

There are other product data sheets that I wrote for WCI on this page.

http://www.strategicwordsmith.biz/productdatasheets.html

To contact WCI (www.wci.com) call Kyle Kelly at (206) 219-5701, or email him at kyle.kelly@wci.com. Kyle can answer any questions about SIP Trunking vs. IP phones in relation to your specific business needs.

Let me know if I can help you in any way.

Robert Lindsay
www.strategicwordsmith.biz